Metrics, measures, statistics, and other items of data may be visualized using a variety of techniques that assist an analyst in recognizing and/or understanding characteristics of organizations, systems, and any other entity for which data may be gathered. For example, various aspects of the operation of computer systems may be monitored to increase reliability, reduce security breaches, and anticipate possible operational issues. For instance, web logs generated by a web server providing access to a web site may be monitored to identify the Internet protocol (“IP”) addresses of computers accessing the web site. In another example, operating characteristics, such as central processor unit (“CPU”) and memory usage, may be monitored to understand the performance and use of a computer system.
Data items often change over time. For example, many operational characteristics of computing systems change over time. For instance, CPU usage may increase or decrease continually based on the type and number of processes being executed by the CPU. In a similar manner, memory usage also typically varies continually based upon the particular processes being handled by the CPU at any given time.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section. Similarly, issues identified with respect to one or more approaches should not assume to have been recognized in any prior art on the basis of this section, unless otherwise indicated.